XCMG has released the "Safe-Lock" structural health monitoring system for its QY25K series truck-mounted cranes. In rough terrain lifting, the boom is subjected to complex dynamic loads that are difficult for the operator to perceive visually. Traditional moment limiters only protect against tipping; they do not protect the boom structure itself from fatigue cracks caused by bending moments.
The Safe-Lock system utilizes "Fiber Bragg Grating" (FBG) strain sensors embedded directly into the boom plates during manufacturing. These sensors are immune to electromagnetic interference and can measure micro-strain (deformation) with high precision. The system monitors the "Boom Bending Deflection" in real-time.
If the system detects that the boom deflection exceeds the elastic limit (indicating the boom is bending too much under a side load or improper outrigger setup), it triggers a "Structural Overload" alarm, separate from the weight load alarm. It forces the telescopic cylinder to lock, preventing further extension that could cause permanent deformation.
Furthermore, the system features "Ground Condition Assessment." By analyzing the pressure fluctuation in the telescopic cylinder when the boom is lowered, the system estimates the stiffness of the ground under the outriggers. If the ground is soft (e.g., backfilled soil), the system automatically reduces the rated lifting capacity by 15% to account for the potential settling of the outriggers. This "active structural protection" significantly extends the fatigue life of the boom, reducing maintenance costs for rental companies.
